SHORT TERM /THROUGH THIS AFTERNOON/
Issued at 230 AM EDT Wed Sep 11 2024

Weak shortwave apparent on GOES 16 water vapor imagery has been progressing through the region tonight. Scattered shower activity has mostly ended across the forecast area, but upstream showers in Wisconsin continue to press toward the forecast area. As we progress through the remainder of the overnight period, these showers will continue pressing northeast into the forecast area. I expect some spotty showers across the central and eastern portions of Upper Michigan. Overnight temperatures so far have fallen into the 50s interior with some spotty low 60s, and low to mid 60s by the lakeshores. There may be some additional cooling overnight, but coolest conditions should still be in the 50s.

Today, expect drying to take hold with clearing skies spreading across the forecast area. Warm airmass overhead will enable surface temps to climb into the 80s save for the southern portions of the eastern counties, which will be moderated some by southerly flow off Lake Michigan. There, highs look to peak in the mid to upper 70s.

LONG TERM /TONIGHT THROUGH TUESDAY/
Issued at 230 AM EDT Wed Sep 11 2024

The pattern over CONUS amplifies in response to a deep trough pressing into the west today, which helps reinforce ridging across the eastern half of CONUS. Guidance continues to suggest a long term forecast period beginning tonight that will be dominated by this anomalous ridging, which will promote a dry period aided by the continued warm airmass through the end of the traditional work week.
By Friday, guidance suggests the ridge axis will be centered over the Great Lakes, thereby blocking Francine's tropical remnants as they try to inch their way north into the middle Mississippi River Valley. By Saturday, consensus is that the ridge axis shifts eastward as a closed low lifts north through Saskatchewan and Manitoba. A shortwave embedded within this trough further south over Nebraska/Iowa, fueled by Francine's remnants, may lift northeastward along the ridge's western flank. Early next week, the pattern re- amplifies with deep and broad troughing over the western half of CONUS and ridging parked over the mid-Atlantic/New England states.
Much like the precip potential this weekend, much will depend on the spatial extent of ridging. If the ridge is a little more compressed or further north, this could open our forecast area to multiple shots of precip beginning mid weekend and next week. Another complication could be another tropical system riding up the east coast into this ridge. At this point, will maintain NBM pops, which does a good job of highlighting my low confidence.

Temperatures in the period will be above normal. 850mb temps climb near 17C and hover near there into the weekend. They may cool slightly by next week, but with there being uncertainty in the ridge axis' position, there's less confidence about that. However, despite this, confidence is high (>75%) that we will continue to see above normal temps early next week. Expecting widespread upper 70s and 80s for Upper Michigan during the day and overnight lows in the 50s interior/near 60 lakeside.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/
Issued at 721 AM EDT Wed Sep 11 2024

VFR conditions will prevail in this TAF period. Tonight, fog/mist may develop over central Upper Michigan. It was left out of this TAF because recent HRRR suggests probability of impacts occuring at KSAW is low (<25%).

MARINE
Issued at 230 AM EDT Wed Sep 11 2024

Ridging over the region will support winds mostly 20kts or lower in into the weekend. This weekend, an amplified pattern builds in and its possible multiple systems may lift into the region beginning mid- weekend and into the first half of next week. However, much will depend on the strength and position of the mid-level ridge this weekend though. Given this uncertainty, confidence is low (<25%).

MQT WATCHES/WARNINGS/ADVISORIES
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.